she is david petraeus's biographer. she is a 40-year-old army officer with a husband and two children who spent more than a year interviewing him for her book. broadwell was sending harassing e-mail's to petraeus's associates including another woman. >> the fbi was investigating her -- his biographer. >> it ended up being difficult for both of us. >> it began after one or more complaints from petraeus's associates. abc news says in the course of their investigation they discovered e-mail. >> it is a tragedy for the nation, a tragedy for the organization, a tragedy for the petraeus family. >> the fbi was initially concerned that security had been breached. but petraeus and broadwell were simply having an affair, irresponsible behavior in the view of some subordinates. >> if they found out you were having an affair, they could use that against you. >> sometimes it is sad what people do in their careers and what they do in their lives because of those things. >> sources tell abc news that there was concern among the petrae